Camera synchronizer



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ied ot. 25, 1940 P. K. MGGALL EI'AL CAMERA sYNcHoNIzER Au-g. 11,1942.

Patented Aug. v1l, 1942.

UNITED STATES PATENT Y OFFICE a 23,292,953 Y v CAMERA srNCnaoNIzEa Philip K. McGall, Orange, and Robert H. Dealtry,

Berkley Heights, N. J., assignors to Samuel Mendelsohn, Montclair, N. J. Application OCtObel' 23, 194,.Selil N0. 362,364 (ci. sv- 29) Y 5 Claims.

The present invention relates to synchronizers for completely opening a camera shutter at the moment of peak intensity from a photoash lamp and particularly to such a device which is ex It is accordingly an object of the present in( vention to provide a synchronzer for camera shutters which is simple in construction and economical to manufacture.

Another object of the present invention is the provision of a simply constructed synchronizerfor camera shutters which can be readily installed by the average amateur photographer on substantially any type of camera.

' Still further objects of the present invention will become obvious to those skilled in the art by reference to the accompanying drawing wherein:

Fig. 1 is a front elevational view of a camera provided with a synchronizer constructed in accordance with the present invention;

Fig. 2 is a cross-sectional view on an enlarged scale of the synchronizer of the present invention and as shown in Fig.y 1; f

Fig. 3 is a cross-sectional view taken .on the line III- III of Fig. 2;

Fig. 4 is a cross-sectional view taken on the line IV-IV of Fig. 2;

Fig. 5 is a fragmentary elevational View of the present synchronizer as shown in Fig. 2, and

Fig. 6 is a diagrammatic illustration of the electrical circuit employed in the synchronizer of the present` invention.

Referring now to the drawing in detail a synchronizer 5 constructed in accordance with the present invention is shown Iin Fig. 1 attached to the shutter 6 of a camera 1. A metallic casing 8, housing a pair of dry cell batteries 9 (Fig. 6) is shown aixed to the camera by any suitable means, such as by a bracket I0. The top of the casing is provided with a socket 'supporting a photoflash lamp I2 whichis provided with a re- .flector I3 for `directing the light from the lamp toward the object t be photographed.

By reference now more particularly to Fig. 2, it Will be noted that the synchronizer comprises a cylindrical metallic member I4 closed at one end by a plug I5 which is held in place by a screw or the like I6. In a similar manner the opposite end of the cylindrical member I4 is closed by a plug I1 held in place by a screw I8 and this latter plug protrudes beyond the end of the cylindrical member I4 where it is provided with an annular groove I9 and an annular recess 20.

This annular recess 20 telescopically receives a threaded thimble 22 which screws into the camera shutter in place of the usual ttng attached -to the cable release. An annular groove 23, similar to the groove I9, is provided in the thimble 22 and in order to hold the latter in place a spring clip 24, secured to the screw I8 passes through a slot 25 inthe groove I9. As shown, the spring clip I24 extends longitudinally of the cylindrical l member I4 for a substantial distance and is then bent angularly through an opening 26'in the Wall of the cylindrical member to form a stop pin 21.

Disposed interiorly of the member I4 is a v plunger 28 of substantially less diameter than the cocked position, a coil spring 32 is disposed between a. longitudinal bore 33 in the plunger and a recess 34 ein the end plug 'I5 so as to be cornpressed when the plunger is in latched position as shown in Fig. 2.

The larger/ area surface 30 is engaged by a shutter actuating member comprising an annular lug 35 secured to an annular block 3E and having an angular end surface r31 which coincides with the larger area surface 3U ofthe plunger 28. A push rod 38 issecured to the block 36 and extends through the thimble 22 a suflicient distance to trip the camera shutter 6 when the thimble is screwed in place. To prevent gravitation of the block 36 and disengagement of the angular surface 31 from the plunger surface 30, a second coil spring 39 is provided between the underside of the block 35 and the end plug I1.

As shown more clearly in Figs. 3 and 4, a, short rod 40 passes through the block 36 and through longitudinally extending slots 42 and 43 in the cylindrical member I4 which is grasped by the ngers of the operator to compress the spring 32 and latch or cock the plunger 28 in engagement with the stop pin 21. For the purpose of tripping the synchronizer a solenoid 44 is secured to the cylindrical member I4 in any suitable manner and in order to increase the effect of its magnetism when energized, the iron core 45 of the solenoid extends through a longitudinal slot 46 in the member Ml so as to dispose the core i5 in closer proximity to the plunger 28. As can be seen in Fig. 6 one end of the solenoid winding is grounded by being connected to the metallic parts of the device as is one side of the batteries Q and the shell of the socket for the photoflash lamp i2. Inasmuch as the other end of the solenoid winding as well as the center contact of the photofiash lamp socket are connected to the other side of the batteries 9 upon closure o the switch di carried by the battery casing 8, the solenoid and photoash lamp are thus simultaneously energized.

Upon energization of the solenoid dll, the plunger 28 is moved laterally within the cylindrical member It toward the solenoid a distance sumcient to cause the stop pin 2l to disengage the angular surface 29. The potential energy stored within the compressed spring 32 accordingly causes rapid downward movement of the plunger 2S which naturally carries with it the shutter actuating member so that the push rod 3% opens the camera shutter.

The parts of the synchronizer, and particularly the strength of the compression spring 32 and the weight of the plunger 23, the inertia of which must be overcome, are'so designed that by the time they go through their cycle of operation to completely open the camera shutter t the photoash lamp, which has a known (time lag, will have reached its moment of peak intensity.

Following the taking of an exposure the operator merely grasps the rod l0 with his fingers and raises the shutter actuating member which again compresses the spring 32. Moreover, due to the coinciding angular surfaces 3l and 30 on the shutter actuating member and on the plunger 28, the latter is first forced laterally toward the solenoid because of the thrust exerted enabling it to pass the stop pin 2l until the smaller` angular surface'area 29 is in alignment with the pin 21 which then retains the plunger in cocked" position upon removal of the operators lingers.

It should also be noted that rotary movement of the shutter actuating member is prevented by the rod 40 protruding through the longitudinal slots 42 and 43. Likewise rotary movement of the plunger 28 is prevented by the tension exerted by the spring 32 both in a longitudinal direction and in a radial direction so that there is no possibility of the coinciding surfaces 30 and 31 getting out of alignment.

It thus becomes obvious to those skilled in the art that a synchronizer for camera shutters is herein provided which is exceptionally simple in construction and economical to manufacture. Moreover, because of its simplicity it can be readily attached to substantially any make of camera by the average amateur photographer and once adjusted at the factory it is substantially foolproof and will maintain accurate synchronization for practically the entire life of the synchronizer.

Although one specific embodiment of the present invention is herein shown and described, it

is to be understood that other modificationsv ter, a shutter lactuating member in said casing adapted to bemoved to cause opening of said camera shutter, a latch member carried by said casing, potential energy storage means in said casing, a plunger of preselected weight and operable to store energy in said energy storage means and movable into engagement With said latch member, and a solenoid attached to said casing and energizable simultaneously with the photoash lamp to overcome the inertia of said plunger and cause lateral movement thereof and disengagement of said plunger from said latch member to render said energy storage means effective to cause longitudinal movement of said plunger with attendant movement of said shutter actuating member to open said camera shutter.

2. A synchronizer for opening a camera shutter simultaneously with the moment of peak intensity of a photo-flash lampl comprising a casing detachably connected to the camera shutter, a shutter actuating member in said casing adapted to be moved to cause opening of said camera shutter, a latch member carried by said casing, a compression spring in said casing, a plunger of preselected weight in said casing and manually movable into engagement with said latch ymember and operable to compress said spring to condition said synchronizer for operation, and a solenoid attached to said casing and energizable simultaneously with the photoash lamp to overcome the inertia of said plunger and cause lateral movement thereof and disengagement of said plunger from said latch member to render said spring effective to cause longitudinal `movement of said plunger with attendant movement of said shutter actuating member to open said camera shutter.

3. A synchronizer for opening a camera shutter simultaneously with the moment of peak intensity of a photoiash lamp comprising a casing detachably connected to the camera shutter, a shutter actuating member in said casing adapted to be automatically moved to cause opening of said camera shutter, a spring pressed plunger of preselected weight in said casing adapted to be tensioned by manual movement of saidshutter actuating member and operable upon release thereof to cause automatic movement of said shutter actuating member with attendant opening of said camera shutter, a latch member engageable with said plunger for retaining the latter under tension ready for operation, and a solenoid carried by said casing provided with an iron core adjacent an opening in said casing in juxtaposition to said plunger and energizable simultaneously with the photoash lamp to overcome the inertia of said plunger and cause lateral movement thereof and disengagement of said plunger from said latch member to render said' plunger effective to automatically move said shutter actuating member.-

4. A synchronizer for opening a camera shutter simultaneously with the moment of peakintensity of a photoash lamp comprising a casing detachably connected to the camera shutter, a shutter actuating member in said casing adapted to be automatically moved to cause opening of said camera shutter, a latch member carried by said casing, a compression spring in said casing, a plunger of preselected weight in said casing detachably connected to the camera shuting movable rearwardly of said latch member.

and into engagement therewith upon movement of said shutter actuating member a'nd operable to compress said spring to condition said syn- 2,292,953 .chronizer for operation, said shutter actuating member and said plunger being provided with complementary angular surfaces to cause lateral movement of said plunger until the latter passes rearwardly of said latch member into engagement therewith, and a solenoid attached to said casing and energizable simultaneously with the photoflash lamp to overcome the inertia of said plunger and cause lateral movement thereof and disengagement of said plunger from said latch member to render said spring eiective to cause longitudinal movement of said plunger with attendant automatic movement of said shutter actuating member to open said camera shutter.

5. A synchronizer for opening a camera shutter simultaneously with the moment of peak intensity of a photoilash lamp comprising a casing detachably connected to the camera shutter, a shutter actuating member in said casing adapted to be automatically moved to cause opening of said camera shutter comprising a spring pressed head carried by a shutter operating rod to prevent gravitation of said member, a latch member carried by said casing, a compression spring in said casing, a plunger of preselected weight in said casing and engageable with said latch member upon manual movement of said shutter actuating member longitudinally of said casing with attendant compression of said spring to condition said synchronizer for operation, said spring pressed head and said plunger being provided with complementary angular surfaces engageable with each other to cause a slight lateral movement of said plunger relative to said casing until the plunger passes rearwardly of said latch member into engagement therewith, and a solenoid attached to said casing and energizable simultaneously with the photoflash lamp to overcome the inertia of said plunger and cause lateral movement thereof and disengagement of said plunger from said latch member to render said spring effective to cause longitudinal movement of said plunger with attendant movement of said shutter actuating member to open said camera shutter. l

PHILIP K. McGALL.

ROBERT H. DEALTRY. 

